I'm starting to upgrade my home office and bought Asus Z9PE-D8.
Plan is to integrate board to my upcoming desk.
Currently I'm aiming at E5 2687's (1 at a time) + evga 570 2.5gb (already have)
As components are going to reside inside desk I started thinking about wc'ing whole rig.
As computer desk is near master bedroom, I'm looking to use GT 800 rpm fans on radiators for quiet result.
I'm however not sure on how much radiator area I would need? I'm thinking on using 2 times 360's but are those enough?
Thank you for your replies.

The two 360's would absolutely be enough, especially because you need it to be quiet. The extra surface area over the standard (1x120mm rad space per heat source) along with a good low rpm radiator like an SR1 or an RX series will allow you to adequately cool a 4p xenon rig along with the 570 with no issues whatsoever. Just make sure you pick up a good, low FPI rad like an SR1 or RX360. Good luck